Vinyl polyethylene elastomer as well as synthesis method and synthesis equipment thereof

Abstract

The invention relates to the technical field of olefin polymerization, in particular to a vinyl polyethylene elastomer as well as a synthesis method and synthesis equipment thereof. According to the synthesis method provided by the invention, the EPOE can be synthesized in one step by taking ethylene as a raw material and adopting the nickel-based diimine ligand main catalyst and the composite cocatalyst. According to the synthesis method disclosed by the invention, the most cheap mixture of aluminum alkyl and the assistant is adopted as the composite promoter, so that the production cost is reduced, and based on the three-section cascade reaction, a competitive reaction of a borate assistant and aluminum alkyl assistant does not exist, the solid content of a reaction product can be increased, and the yield of the product is increased. The utilization efficiency of the catalyst and the conversion per pass of ethylene are increased, the product performance is not different from that of C4 / C8POE, and POE products in the market can be completely replaced. The synthesis method disclosed by the invention adopts the synthesis equipment disclosed by the invention for synthesis, the synthesis can be continuously and stably carried out, the phenomenon that gel and solid PE block a pipeline does not exist, and the synthesis method belongs to a continuous efficient catalysis process.

Description

Technical Field

[0001] The present invention relates to the technical field of olefin polymerization, in particular to an ethylene polyethylene elastomer and a synthesis method and synthesis equipment thereof. Background Art

[0002] Branched polyethylene elastomers are elastomeric materials derived from the homopolymerization or copolymerization of ethylene monomers with α-olefins or certain cycloolefins. Compared to conventional polyethylene, branched and hyperbranched polyethylenes offer advantages such as low viscosity, low density, good rheological properties, and functional end groups amenable to further modification. These advantages have led to their widespread application in nanomaterials, polymer blends, coatings, thin films, polymer liquid crystals, and drug delivery systems. Among these, the best performing polyethylene elastomers (POEs) are those derived from the copolymerization of ethylene with α-olefins (1-butene, 1-hexene, and 1-octene). These elastomers, in addition to sharing the characteristics of other branched polyethylenes, also possess excellent mechanical properties, toughness, and durability. Currently, the most preferred POE synthesis method utilizes a single-active-center metallocene catalyst and modified methylaluminoxane as the catalytic system for the polymerization of ethylene and α-olefins. However, this method suffers from high catalytic costs, demanding synthesis conditions, difficulty in active polymerization at room temperature, and difficulty in copolymerizing with polar monomers. Similarly, the low insertion rate of α-olefins requires a large amount of α-olefin as raw material, further increasing polymerization costs.

[0003] Ethylene polyolefin elastomer (EPOE) is a high-performance material that can be prepared using only ethylene as raw material, without the use of α-olefins (1-butene, 1-hexene, 1-octene). In terms of performance, EPOE, like POE, can increase the toughness of elastomer materials, has excellent rheological properties and photovoltaic properties, and other properties are similar to POE. It is widely used in automotive parts, photovoltaic films, aerospace, cable construction and other fields. In terms of cost, EPOE synthesis catalysis uses independently developed nickel-based catalysts combined with different co-catalysts to synthesize elastomer materials with different performance grades. At present, most metallocene catalysts in China are imported, and nickel-based catalysts have broken the foreign monopoly. In addition, EPOE only uses ethylene as raw material, saving a large amount of imported α-olefins and greatly reducing production costs. From the perspective of policy and market, EPOE complies with the country's localization of high-end polyolefins, and with its outstanding performance and low-cost advantages, it can quickly occupy the domestic market. It is the first choice of many materials and has promoted the overall domestic POE industry to a new stage of high-quality development. However, its disadvantages are also obvious. First of all, it has high requirements for device design and the process is relatively cumbersome and complicated. Furthermore, ethylene, as an inserted monomer, has a low degree of branching (less than 30 branches / 1000°C), resulting in high viscosity elastomers and the inability to produce high-polymer PE in a continuous and stable manner. Furthermore, its low solids content has a certain impact on product performance, making it unable to replace finished POE in the modification field.

[0004] Based on the above shortcomings, there is an urgent need to disclose a synthesis method of EPOE with a simple production process, low equipment investment and low catalytic cost. Summary of the Invention

[0005] In view of this, the present invention aims to provide an ethylene-based polyethylene elastomer, a synthesis method, and a synthesis apparatus. The preparation method provided by the present invention has low requirements for equipment and raw materials, is simple and easy to operate, and enables continuous and stable production, reducing time, labor, and energy costs. The resulting ethylene-based polyethylene elastomer has a high solids content and exhibits comparable performance to POE.

[0006] The present invention provides a method for synthesizing an ethylene-based polyethylene elastomer, comprising the following steps:

[0007] S1) in the presence of ethylene, sequentially carrying out a first stage reaction, a second stage reaction and a third stage reaction with a nickel-based bisimine ligand main catalyst and a composite co-catalyst; the composite co-catalyst is a mixture of an alkyl aluminum and a borate auxiliary agent;

[0008] S2) subjecting the reaction product obtained in step S1) to a cyclopentane reaction to obtain an ethylene-based polyethylene elastomer.

[0009] The present invention first performs step S1). Specifically, in the presence of an ethylene solution, a mixed solution of a nickel-based bisimine ligand main catalyst and a composite co-catalyst is sequentially subjected to a first-stage reaction, a second-stage reaction, and a third-stage reaction. More specifically, the present invention first performs a first-stage reaction on the mixed solution of the nickel-based bisimine ligand main catalyst and the composite co-catalyst in the presence of an ethylene solution, then performs a second-stage reaction on the product obtained from the first-stage reaction in the presence of an ethylene solution, and then performs a third-stage reaction on the product obtained from the second-stage reaction in the presence of an ethylene solution.

[0010] The ethylene described in the present invention is an ethylene solution, and the mass ratio of the ethylene to the ethylene solution is 0.1 to 0.5, preferably 0.2 to 0.3. The reaction concentration of the nickel-based bisimine ligand main catalyst described in the present invention is 5 μmol / L to 50 μmol / L, preferably 15 μmol / L to 25 μmol / L; the reaction concentration of the nickel-based bisimine ligand main catalyst refers to the concentration of the nickel-based bisimine ligand main catalyst in the reaction solution of the first, second, and third stages of the reaction, respectively. The composite co-catalyst described in the present invention is a mixture of an alkyl aluminum and a borate auxiliary agent, the molar ratio of the alkyl aluminum to the borate auxiliary agent being (100 to 800):1, preferably (200 to 500):1; the molar ratio of the alkyl aluminum to the nickel-based bisimine ligand main catalyst being (200 to 2000):1, preferably (500 to 1000):1.

[0011] The present invention has no specific requirements for the ethylene in the ethylene solution, and it can be polymerization-grade ethylene. The ethylene solution of the present invention is obtained by mixing ethylene with a solvent before reaction; the solvent is selected from one or more aliphatic or aromatic solvents, such as one or more of n-hexane, cyclohexane, n-heptane, isooctane, or toluene; preferably cyclohexane and n-hexane.

[0012] The mixed solution of the nickel-based bisimine ligand main catalyst and the composite co-catalyst of the present invention is obtained by mixing the nickel-based bisimine ligand main catalyst and the composite co-catalyst in a solvent. The solvent is the same as described above and will not be repeated here. The composite co-catalyst of the present invention is a mixture of an alkyl aluminum and a borate auxiliary agent, obtained by mixing an alkyl aluminum and a borate auxiliary agent. Preferably, the alkyl aluminum is selected from one or more of trimethyl aluminum, triethyl aluminum, diethyl aluminum chloride, and triisobutyl aluminum; and the borate auxiliary agent is selected from one or more of triphenyl carbon tetrakis (pentafluorophenyl) borate, N,N-dioctadecylanilinium tetrakis (pentafluorophenyl) borate, and N,N-dihexadecylanilinium tetrakis (pentafluorophenyl) borate. In one embodiment of the present invention, the composite co-catalyst is a mixture of trimethyl aluminum and N,N-dihexadecylanilinium tetrakis (pentafluorophenyl) borate. In another embodiment of the present invention, the composite co-catalyst is a mixture of triethyl aluminum and triphenyl carbon tetrakis (pentafluorophenyl) borate.

[0013] The nickel-based bisimine ligand main catalyst of the present invention is one or more of the most common nickel-based bisimine ligand catalysts, which can be directly obtained by purchase or obtained by independent synthesis. The synthesis method refers to relevant patents such as CN117902999A and CN107759641A. Preferably, the nickel-based bisimine ligand main catalyst of the present invention is selected from 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,4,6-trimethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-diisopropylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-diphenylmethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl- One or more of 2-(4-methylphenylimino)-3-phenyliminobutane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)acenaphthenequinone nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)pyridine nickel bromide, 2-(2,6-bis(4-methoxy)benzyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide, and 2-(2,6-diphenylmethyl-4-fluorophenylimino)-3-(2-methyl-4-fluorophenylimino)butane nickel bromide.

[0014] The reaction pressures of the first, second, and third stages of the present invention are independently 0.5 MPa to 6.5 MPa, preferably 2 MPa to 4 MPa. The temperatures of the first, second, and third stages of the present invention are independently 40° C. to 90° C., preferably 60° C. to 70° C.; and the durations of the first, second, and third stages of the reaction are independently 5 min to 20 min, preferably 10 min to 15 min.

[0015] In certain embodiments of the present invention, an ethylene solution is passed into a first-stage reactor, a second-stage reactor, and a third-stage reactor, and then a mixed solution of a nickel-based bisimine ligand main catalyst and a composite co-catalyst is passed into the first-stage reactor, and the first-stage reaction is carried out by controlling the temperature, pressure, and residence time of the reaction liquid in the first-stage reactor; the product obtained from the first-stage reaction is passed into a second-stage reactor, and the second-stage reaction is carried out by controlling the temperature, pressure, and residence time of the reaction liquid in the second-stage reactor; the product obtained from the second-stage reaction is passed into a third-stage reactor, and the third-stage reaction is carried out by controlling the temperature, pressure, and residence time of the reaction liquid in the third-stage reactor; preferably, the liquid level of the reaction liquid in the first-stage reactor accounts for 60% to 90% of the volume of the first-stage reactor, and most preferably 70% to 80%; the liquid level of the reaction liquid in the second-stage reactor accounts for 60% to 90% of the volume of the second-stage reactor, and most preferably 70% to 80%; the liquid level of the reaction liquid in the third-stage reactor accounts for 60% to 90% of the volume of the third-stage reactor, and most preferably 70% to 80%.

[0016] After performing step S1) in the present invention, the reaction product obtained in step S1) is subjected to a loop reaction to obtain an ethylene-based polyethylene elastomer. Specifically, the reaction product obtained in step S1) is subjected to a loop reaction, and then the product after the loop reaction is subjected to gas-liquid separation to remove gas components and solvent to obtain a reaction liquid. The reaction liquid is then subjected to flash separation to further remove the solvent to obtain a gel product. Finally, the gel product is deashed and dried to obtain the ethylene-based polyethylene elastomer; the gas components and solvent can be recycled. The pressure of the loop reaction in the present invention is 0.5 MPa to 6.5 MPa, preferably 2 MPa to 4 MPa. The temperature of the loop reaction in the present invention is 40°C to 90°C, preferably 60°C to 70°C; and the loop reaction time is 10 to 50 minutes, preferably 25 to 35 minutes.

[0017] In certain embodiments of the present invention, the reaction product obtained in step S1) is introduced into a loop tube reactor for loop reaction, and then the product after the loop tube reaction is introduced into a separatory tank for gas-liquid separation to remove gas components and solvent to obtain a reaction liquid, and then the reaction liquid is introduced into a flash tank for flash separation to further remove the solvent to obtain a gel product, and finally the gel product is deashed and dried in an extruder to obtain an ethylene-based polyethylene elastomer; the solvent component is introduced into a solvent recovery tank for recovery; and the gas component is returned to the first-stage reactor in step S1).

[0018] In the synthesis method of the ethylene-based polyethylene elastomer of the present invention, the ethylene, nickel-based bisimine ligand main catalyst, alkyl aluminum and borate auxiliary agent and the used solvent can all be purified before the reaction.

[0019] The synthesis method of the ethylene-based polyethylene elastomer of the present invention can continuously and stably produce ethylene-based polyethylene elastomer products with excellent performance. Tests have shown that the synthesis method of the ethylene-based polyethylene elastomer of the present invention can continuously and stably produce for more than 1200 hours, and the catalytic activity is 28×10 6 ~45×10 6 g / molNi·h, and the ethylene single-pass conversion efficiency is above 95%.

[0020] The present invention also provides an ethylene-based polyethylene elastomer, which is obtained by any of the above-mentioned synthesis methods. The weight average molecular weight of the ethylene-based polyethylene elastomer is 15×10 4 ~65×10 4 , molecular weight distribution is 2.1-4.2, branching degree is 100-120, tensile strength>5MPa, elongation at break>900%.

[0021] The present invention also provides a synthesis device for ethylene-based polyethylene elastomer using any of the above-mentioned synthesis methods, comprising a reaction unit, wherein the reaction unit sequentially comprises:

[0022] The first stage reactor;

[0023] a second stage reactor connected to the first stage reactor;

[0024] a third stage reactor connected to the second stage reactor;

[0025] A loop pipe connected to the third stage reactor.

[0026] The first-stage reactor of the present invention is used to carry out the first-stage reaction described in the aforementioned synthesis method; the second-stage reactor is used to carry out the second-stage reaction described in the aforementioned synthesis method; the third-stage reactor is used to carry out the third-stage reaction described in the aforementioned synthesis method; and the loop pipe is used to carry out the loop pipe reaction described in the aforementioned synthesis method. The first, second, and third-stage reactors of the present invention form a series of reactors connected by a bottom pipeline; the discharge pipeline at the bottom of the third-stage reactor is connected to the loop pipe. The first-stage reactor of the present invention is equipped with feed lines for ethylene, a nickel-based bisimine ligand primary catalyst, an alkyl aluminum and borate auxiliary agent, and the solvent used.

[0027] The synthesis apparatus of the present invention also includes a raw material purification system connected upstream of the first-stage reactor. Specifically, the discharge line of the raw material purification system is connected to the feed line provided on the first-stage reactor. The raw material purification system is used to purify the ethylene, nickel-based bisimine ligand primary catalyst, alkyl aluminum, borate auxiliary agent, and solvent used in the aforementioned synthesis method prior to the reaction.

[0028] The synthesis equipment of the present invention further comprises a recovery unit, which is connected to the reaction unit and specifically comprises:

[0029] a separator connected to the pipe ring;

[0030] a flash tank connected to the separator tank;

[0031] An extruder is connected to the flash tank.

[0032] The feed line of the separatory tank of the present invention is connected to the discharge line of the ring tube, receives the reaction solution leaving from the discharge line of the ring tube, performs gas-liquid separation on the reaction solution, removes the gas components and solvent in the reaction solution, and the remaining reaction liquid leaves through the discharge line provided on the separatory tank. The feed line of the flash tank of the present invention is connected to the discharge line of the separatory tank, receives the reaction solution leaving from the discharge line of the separatory tank, performs flash separation on the reaction solution, further removes the solvent in the reaction solution to obtain a gel product, and the gel product leaves through the discharge line provided on the flash tank. The extruder of the present invention is connected to the discharge line of the flash tank, and the function of the extruder is to deash and dry the gel product leaving from the discharge line of the flash tank to obtain a dry ethylene-based polyethylene elastomer.

[0033] The recovery unit of the present invention further comprises:

[0034] a solvent recovery tank connected to the liquid separator and the flash tank respectively;

[0035] An ethylene return pipeline is provided between the liquid separation tank and the first stage reactor;

[0036] The ethylene return pipeline is provided with a return line compressor.

[0037] The solvent recovery tank of the present invention is used to recover the solvent obtained by gas-liquid separation of the reaction solution in the separatory tank and the solvent obtained by flash separation of the reaction solution in the flash tank. The ethylene return pipeline of the present invention is used to recover the gaseous components obtained by gas-liquid separation of the reaction solution in the separatory tank. The gaseous components pass through the return line compressor provided on the ethylene return pipeline and enter the first-stage reactor from the separatory tank for recycling.

[0038] The synthesis equipment of the present invention further includes a heat preservation device disposed on the connecting pipelines of the synthesis equipment. By controlling the connecting pipelines of the synthesis equipment, the heat preservation device of the present invention can prevent gel precipitation and pipeline blockage. The heat preservation device of the present invention controls the temperature of the connecting pipelines of the synthesis equipment to 60°C to 80°C, preferably 70°C to 75°C.

[0039] There are no special restrictions on all the equipment and materials used in the synthesis equipment of the present invention, and equipment and materials familiar to those skilled in the art can be used.

[0040] The present invention provides an ethylene-based polyethylene elastomer and a synthesis method and synthesis equipment thereof. The synthesis method provided by the present invention uses ethylene as a raw material, adopts a nickel-based diimine ligand main catalyst and a composite co-catalyst, and can synthesize EPOE in one step. The composite co-catalyst used in the synthesis method of the present invention adopts a mixture of the cheapest alkyl aluminum and an auxiliary agent, which not only reduces the production cost, but also is based on a three-stage series reaction, and there is no competitive reaction between the borate auxiliary agent and the alkyl aluminum auxiliary, which can increase the solid content of the reaction product, increase the utilization efficiency of the catalyst and the single-pass conversion rate of ethylene, and the product performance is no different from that of C4 / C8POE, and can completely replace the POE products on the market. The synthesis method of the present invention is simple and easy to operate, and the catalyst cost, raw material cost, equipment cost, and energy consumption cost are greatly reduced. The synthesis method of the present invention is synthesized using the synthesis equipment of the present invention, and can be carried out continuously and stably, and there is no phenomenon of gel and solid PE blocking the pipeline, which is a continuous and efficient catalytic process.

[0041] The present invention has the following advantages:

[0042] (1) The process of the present invention is simple, the equipment investment is low, the operation is easy, and the cost is low. It can be applied to any reaction in the field of olefin catalysis, and shares a common purification and public system. It only uses ethylene as a raw material, and the solvent and ethylene are recycled and reused, which can greatly reduce costs.

[0043] (2) This process is a continuous process. The catalysts are all common catalysts with low cost. The mixture of the catalyst and the additive can effectively inhibit the production of high-polymer PE, avoid clogging the pipeline, and enable the process to operate continuously and stably.

[0044] (3) The present invention adopts multiple reactors connected in series and adds a loop reactor, which can effectively improve the conversion rate of ethylene and the catalytic efficiency of the catalyst; for the product, the solid content of the product is increased, which is beneficial to the catalytic activity and product performance.

[0045] (4) The reaction temperature of this process is consistent with the temperature of the pipeline from the reaction unit to the recovery unit. The pipeline insulation is sufficient only by taking heat from the reactor, which reduces equipment investment and energy consumption of the public system. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The figure is a schematic diagram of the process of synthesizing the ethylene-based polyethylene elastomer of the present invention using the synthesis equipment of the present invention. DETAILED DESCRIPTION

[0047] The present invention discloses an ethylene-based polyethylene elastomer, a synthesis method, and a synthesis apparatus thereof. Those skilled in the art may refer to the contents of this document and appropriately improve the process parameters to achieve the desired results. It should be noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately alter and combine the methods and applications herein without departing from the content, spirit, and scope of the present invention to implement and apply the technology of the present invention.

[0048] The raw materials can all be purchased. The main catalyst adopts a conventional nickel-based diimine catalyst, which can be directly purchased or synthesized by purchasing raw materials. As described in reference patents CN117645552A, CN117843524A, CN117902999A, and CN107759641A, diacetyl and different amines are mixed and stirred in p-toluenesulfonic acid and toluene to synthesize a ligand, and then complexed with nickel bromide in dichloromethane to obtain the main catalyst.

[0049] The present invention will be further described below with reference to the embodiments:

[0050] Example 1

[0051] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide is the main catalyst, N,N-dihexadecylanilinium tetrakis(pentafluorophenyl)borate is the auxiliary agent, trimethylaluminum is the auxiliary catalyst, and the solvent is n-hexane. The reaction concentration of the main catalyst is 20μmol / L, the auxiliary agent and the auxiliary catalyst are mixed in a molar ratio of 1:500 to obtain a composite co-catalyst, and the molar ratio of alkyl aluminum to the main catalyst in the composite co-catalyst is 1000:1. Figure 1 As shown, Figure 1This is a schematic flow diagram of the synthesis of the ethylene-based polyethylene elastomer described in the present invention using the synthesis equipment described in the present invention. The purified raw ethylene and solvent are mixed in a mass ratio of 0.3 and enter reactors (1#, 2#, and 3#), with the reaction pressure reaching 4.0 MPa and the temperature stabilized at 70°C. The main catalyst and composite co-catalyst are each introduced into reactor 1# along with n-hexane in the above ratios. After the volume of the reaction liquid reaches 80% of the reactor volume, the bottom discharge valve is opened and it enters reactor 2#, with a controlled retention time of 10 minutes. Similarly, it enters reactors 2# and 3# in sequence, and the reaction liquid enters a loop pipe with a controlled retention time of 30 minutes. After passing through the loop pipe, the reaction enters a separator for gas-liquid separation. The gaseous ethylene is compressed by a compressor and returned to reactor 1#. The solvent enters a solvent recovery tank, and the liquid enters a flash tank for further separation of the solvent and product. The reaction product enters an extruder for deashing and drying, resulting in a dried EPOE elastomer product, which is then pelletized and tested for performance. The solvent after flash evaporation enters a solvent recovery tank and is reused through a purification system. This process was carried out continuously and stably for 1440 hours. After the reaction pipeline was removed, dry film residues were found on the reactor wall and the pipe wall, which needed to be cleaned with hot solvent. No large amount of solid deposition or blockage was found, and it was easy to clean. The collected products were subjected to comprehensive calculation and test analysis, and the catalytic activity was obtained to be 42×10 6 g / molNi·h, the ethylene single-pass conversion efficiency is above 96.5%, and the weight-average molecular weight of the product EPOE is 26.9×10 4 , molecular weight distribution is 3.0, branching degree is 106, tensile strength is 6.98MPa, and elongation at break is 1004%. In order to verify the stability of the device, we conducted multiple tests with different catalysts and ratios, as shown in Table 1.

[0052] Example 2

[0053] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,4,6-trimethylphenylimino)butanenickel bromide was used as the main catalyst, N,N-dihexadecylanilinium tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, trimethylaluminum was used as the co-catalyst, and n-hexane was used as the solvent. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0054] Example 3

[0055] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,4,6-trimethylphenylimino)butane nickel bromide was used as the main catalyst, triphenylcarbon tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, triethylaluminum was used as the auxiliary catalyst, and the solvent was n-hexane. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0056] Example 4

[0057] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)acenaphthenequinone nickel bromide was used as the main catalyst, triphenylcarbon tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, triethylaluminum was used as the co-catalyst, and the solvent was n-hexane. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0058] Example 5

[0059] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)acenaphthenequinone nickel bromide was used as the main catalyst, triphenylcarbon tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, triethylaluminum was used as the co-catalyst, and cyclohexane was used as the solvent. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0060] Example 6

[0061] 2-(2,6-diphenylmethyl-4-fluorophenylimino)-3-(2-methyl-4-fluorophenylimino)butane nickel bromide was used as the main catalyst, triphenylcarbon tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, triethylaluminum was used as the auxiliary catalyst, and cyclohexane was used as the solvent. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0062] Comparative Example 1

[0063] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide was used as the main catalyst, trimethylaluminum was used as the auxiliary catalyst, the solvent was n-hexane, and no auxiliary agent was added. Other conditions were the same as in Example 1, and the optimal reaction conditions were selected. The results are shown in Table 1.

[0064] Comparative Example 2

[0065] The same performance test was conducted on C4 / C8POE synthesized from the market, and the results are shown in Table 1.

[0066] Comparative Example 3

[0067] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butanenickel bromide was the primary catalyst, N,N-dihexadecylanilinium tetrakis(pentafluorophenyl)borate was the auxiliary agent, trimethylaluminum was the auxiliary catalyst, and n-hexane was the solvent. Different catalyst addition methods were explored. The boron auxiliary agent and the primary catalyst were premixed into a mixed solution and then introduced into the reactor. The auxiliary catalyst was also introduced into the reactor separately. The catalyst ratio was consistent with the above example, and the process conditions remained unchanged. The optimal reaction conditions were selected. The results are analyzed in Table 1.

[0068] Comparative Example 4

[0069] 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)acenaphthenequinone nickel bromide was used as the main catalyst, triphenylcarbon tetrakis(pentafluorophenyl)borate was used as the auxiliary agent, triethylaluminum was used as the auxiliary catalyst, and the solvent was n-hexane. Different catalyst addition methods were explored, and the boron auxiliary agent was premixed with the main catalyst, and the auxiliary catalyst was added to the reactor separately. The catalyst ratio was consistent with the above example, and the process conditions remained unchanged. The optimal reaction conditions were selected. The results are analyzed in Table 1.

[0070] The process results show that the process can be continuously and stably operated for more than 1200 h using different catalysts, feed methods and reaction conditions, and the catalytic activity reaches 30×10 6 g / molNi·h or above, the ethylene single-pass conversion rate is above 95.5%, and the performance of the obtained product is not much different, which is similar to that of C4 / C8POE purchased on the market.

[0071] Table 1

[0072]

[0073] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for synthesizing an ethylene-based polyethylene elastomer, characterized in that: The following steps are involved: S1) in the presence of ethylene, sequentially carrying out a first stage reaction, a second stage reaction and a third stage reaction with a nickel-based bisimine ligand main catalyst and a composite co-catalyst; the composite co-catalyst is a mixture of an alkyl aluminum and a borate auxiliary agent; S2) subjecting the reaction product obtained in step S1) to a cyclopentane reaction to obtain an ethylene-based polyethylene elastomer.

2. The synthesis method according to claim 1, wherein In step S1), the ethylene is an ethylene solution, and the mass ratio of the ethylene to the ethylene solution is 0.1 to 0.5; The reaction concentration of the nickel-based bisimine ligand main catalyst is 5 μmol / L to 50 μmol / L; The molar ratio of the alkyl aluminum to the borate auxiliary agent is (100-800):1; The molar ratio of the alkyl aluminum to the nickel-based bisimine ligand main catalyst is (200-2000):

1.

3. The synthesis method according to claim 1, wherein In step S1), the alkylaluminum is selected from one or more of trimethylaluminum, triethylaluminum, diethylaluminum chloride, and triisobutylaluminum; The borate auxiliary agent is selected from one or more of triphenylcarbon tetrakis (pentafluorophenyl) borate, N,N-dioctadecylanilinium tetrakis (pentafluorophenyl) borate, and N,N-dihexadecylanilinium tetrakis (pentafluorophenyl) borate; The nickel-based bisimine ligand main catalyst is selected from 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,4,6-trimethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-diisopropylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-diphenylmethylphenylimino)butane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-diisopropylphenylimino)butane nickel bromide, One or more of 2-(2,6-diphenylimino)-3-phenyliminobutane nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)acenaphthenequinone nickel bromide, 2-(2,6-diphenylmethyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)pyridine nickel bromide, 2-(2,6-bis(4-methoxy)benzyl-4-methylphenylimino)-3-(2,6-dimethylphenylimino)butane nickel bromide, and 2-(2,6-diphenylmethyl-4-fluorophenylimino)-3-(2-methyl-4-fluorophenylimino)butane nickel bromide.

4. The synthesis method according to claim 1, characterized in that In step S1), the reaction pressures of the first stage reaction, the second stage reaction, and the third stage reaction are independently 0.5 MPa to 6.5 MPa.

5. The synthesis method according to claim 1, characterized in that In step S1), the temperature of the first stage reaction, the second stage reaction and the third stage reaction are independently 40° C. to 90° C., and the time of the first stage reaction, the second stage reaction and the third stage reaction are independently 5 min to 20 min.

6. The synthesis method according to claim 1, characterized in that In step S2), the pressure of the loop reaction is 0.5 MPa to 6.5 MPa.

7. The synthesis method according to claim 1, characterized in that In step S2), the temperature of the loop tube reaction is 40° C. to 90° C., and the time of the loop tube reaction is 10 min to 50 min.

8. An ethylene-based polyethylene elastomer, characterized in that The compound is obtained by the synthesis method according to any one of claims 1 to 7.

9. A synthesis device for ethylene-based polyethylene elastomer using the synthesis method according to any one of claims 1 to 7, characterized in that: It includes, in order: The first stage reactor; a second stage reactor connected to the first stage reactor; a third stage reactor connected to the second stage reactor; A loop pipe connected to the third stage reactor.

10. The synthesis device according to claim 9, characterized in that It also includes a heat preservation device, which is arranged on the connecting pipeline of the synthesis device; The heat preservation device controls the temperature of all connecting lines of the synthesis device to be 60° C. to 80° C.

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